Abstract
A MAP kinase kinase kinase (MAPKKK) was identified in phaeochromocytoma (PC12) cells which reactivated homogeneous MAP kinase kinase (MAPKK) from rabbit skeletal muscle that had been inactivated by incubation with protein phosphatase 2A. Reactivation was accompanied by stoichiometric phosphorylation of MAPKK on a serine residue(s). Following stimulation of PC12 cells with nerve growth factor and chromatography of the extracts on Mono Q, MAP kinase and MAPKK were detected as active phosphorylated enzymes, whereas MAPKKK was inactive and only activated after prolonged storage at 4°C. The results suggest that the activation of MAPKKK by growth factors is likely to occur by a non-covalent mechanism.
Original language | English |
---|---|
Pages (from-to) | 461-465 |
Number of pages | 5 |
Journal | FEBS Letters |
Volume | 314 |
Issue number | 3 |
DOIs | |
Publication status | Published - 21 Dec 1992 |
Keywords
- MAP kinase
- Nerve growth factor
- PC12 cell
- Protein phosphorylation
- Signal transduction
ASJC Scopus subject areas
- Biophysics
- Structural Biology
- Biochemistry
- Molecular Biology
- Genetics
- Cell Biology